package com.itheima.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否已经完成登录
 */
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter  implements Filter {
    //路径匹配器 支持通配符
    private static final AntPathMatcher PATH_MATCHER =new AntPathMatcher();
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request= (HttpServletRequest) servletRequest;
        HttpServletResponse response= (HttpServletResponse) servletResponse;

        //获取本次请求的uri
        String currentUri = request.getRequestURI();
        log.info("拦截到请求:{}",currentUri);
        //定义不需要处理的请求路径
        String[] urls=new String[]{"/employee/login","/employee/logout","/backend/**","/front/**","/common/**",
        "/user/sendMsg","/user/login","/doc.html",
                "/webjars/**",
                "/swagger-resources",
                "/v2/api-docs"
        };
        //判断本次请求是否需要处理
        boolean check = check(currentUri, urls);
        //如果不需要处理,直接放行
        if (check){
            log.info("本次请求{}不需要处理",currentUri);
            filterChain.doFilter(request,response);
            return;
        }
        //判断登录状态,如果已登录直接放行
        if (request.getSession().getAttribute("employee")!=null){
           log.info("用户已登录,用户id为:{}",request.getSession().getAttribute("employee"));
            /**
             * 将当前登录的用户ID存入ThreadLocal
             */
            Long empId= (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);
            //放行
            filterChain.doFilter(request,response);
           return;
        }

        //判断移动端是否登录
        if (request.getSession().getAttribute("user")!=null){
            log.info("用户已登录,用户id为:{}",request.getSession().getAttribute("user"));
            /**
             * 将当前登录的用户ID存入ThreadLocal
             */
            Long userId= (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);
            //放行
            filterChain.doFilter(request,response);
            return;
        }
        //如果未登录返回未登录结果,通过输出流方式向移动端页面相应数据
        log.info("用户未登录");
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }

    /**
     * 路径匹配 检查本次请求是否要放行
     * @param currentUri
     * @param urls
     * @return
     */
    private boolean check(String currentUri, String[] urls) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, currentUri);
            if (match){
                return true;
            }
        }
        return false;
    }
}
